Conventionally, in the field of manufacture of semiconductor devices or the like, there is known a plasma processing apparatus that processes a target substrate such as a semiconductor wafer by generating plasma within a hermetically sealable processing chamber. Further, there is known a plasma etching apparatus as one example of such a plasma processing apparatus.
In such a plasma etching apparatus or the like, plasma etching may cause deposits to adhere on the inside of the processing chamber. The deposits may be peeled off from the inside of the processing chamber and, then, the deposits may be dispersed as particles and be adhered to a semiconductor wafer on which an etching process is being performed. To prevent this problem, conventionally, the inside of the processing chamber has been cleaned periodically.
Further, a cylindrical liner is installed so as to cover a wall surrounding a plasma generation space in the processing chamber, and, then deposits are removed from the inside of the processing chamber by regularly replacing or cleaning the liner after separating the liner (see, for example, Patent Document 1).
Patent Document 1: Japanese Patent Laid-open Publication No. 2008-270595
As stated above, conventionally, the cylindrical liner or the like covering the wall surrounding the plasma generation space has been installed and the liner has been regularly replaced or separated and cleaned.
However, deposits may be adhered not only to the plasma generation space of the processing chamber but also to a portion originally considered to be unreachable by plasma, such as a portion under a baffle plate configured to surround a mounting table for mounting a target substrate thereon and provided with a through hole, a slit, or the like through which a gas exhaust is performed. If deposits are adhered to such a portion and if it is difficult to separate and clean components of the processing chamber, it has been difficult to completely remove the deposits by performing a cleaning process within the processing chamber. Therefore, there has been a problem that it takes a long time to complete the cleaning process.
Furthermore, to install a detachable cover configured to cover such a portion, at least a surface of the cover needs to be made of an insulating material so as to prevent an abnormal electric discharge, and a highly plasma-resistance material should be used for the cover. Therefore, there has been a problem that manufacturing cost is increased.